Tensioning apparatus



Nov. 24, 1964 J. L. BIACH 3,158,052

TENSIONING APPARATUS Filed Oct. 4. 1961 2 Sheets$heet 1 INVENTOR. Ja/m/4. 6/146 BY Kw fi I Nov. 24, 1964 J. L. BIACH 3,153,052

TENSIONING APPARATUS Filed Oct. 4, 1961 2 Sheets-Sheet 2 INVENTOR..ram/ 1. .dfldi @fim MZ M United States Patent 3,158,952 TENSEENINGAPPARATUS John L. Biach, Crantord, N.J., assignor to liiach industries,line, Cranford, N .21., a corporation of New Jersey Filed 0st. 4, 19M,Ser. No. 142,868 2 Claims. (Cl. 81-54) This invention relates to astructurally and functionally improved apparatus by means of which boltsmay be accurately andv uniformly tensioned.

According to one aspect of the invention, the present teachings providean improved and/or alternative structure to that disclosed in my priorUnited States Patent No. 2,866,370 of December 30, 1958, and my pendingapplications on tensioning apparatus, Serial No. 853,554, I

filed November 17, 1959 (now Patent No. 3,015,975), and Serial No.108,645, filed May 8, l96l.

It is a primary object of the present invention to furnish a compactmechanism which may be employed in a space of limited dimensions andwhich, moreover, will be relatively light. Accordingly, the apparatusmay be eificiently used by a single operator.

A further object is that of designing an apparatus for use with boltsand nuts or different sizes; it being necessary to change only a fewminor parts of the assembly to adapt the unit to elements of dilferentdimensions.

Still another object is that of providing a tensioning apparatus whichwill include a simple layout of mechanism embracing relatively fewcomponents each individually rugged and simple in design; those elementsbeing capable of ready grouping to provide a unitary apparatusfunctioning over long periods of time with freedom from alldiiiiculties.

With these and other objects in mind, reference is had to the attachedsheets of drawings illustrating practical embodiments of the inventionand in which:

FIG. 1 is a front elevation of the tcnsioning apparatus;

FIG. 2 is a top plan View thereof;

FIG. 3 is a sectional plan view taken through the base zone along theline 33 of FIG. 1;

FIG. 4 is a sectional side view of a complete assembly; and

FIG. 5 is a view similar to FIG. 4 but showing the unit applied to abolt and nut of different size than that illustrated in FIG. 4.

Referring primarily to FIGS. 1 and 2, the numeral it) indicates the bodyof a housing including a base portion ll. A plate 12 is disposed in linewith the upper face of the housing. The plate and housing are formedwith outstanding ears provided with aligned apertures. Bolts 13 extendthrough the latter and mount springs 13' which bear against the boltheads and housing ears. Accordingly, plate 12 is constantly urgedtowards the housing. An inlet fitting 14 connects with a passageextending through to the interior of the housing. The latter hasprojecting from its front face an annular flange 15 within which thereis housed the body of a shaft 16. Conveniently, that shaft has attachedto its outer end a handle 17.

Referring to FIG. 3 it will be seen that the lower zone of the housinghas its side edges recessed as indicated at 18. In this manner, arelatively extended base contact area 19 is present. As a consequence ofthe recessing as at 18, even with a series of closely spaced bolts 20and nuts 21 being involved, the apparatus may be readily applied to anyone of these without interfering With adjacent assemblies. So applied,the mechanism may be operated to place a selected bolt under tension andbecause of the relatively large area of contact, no distortion of theparts will occur as the housing exerts reaction pressure against thesurface 22 of a part through which bolts Ell extend.

3,158,052 Patented Nov. 24, 1964 Base portion ll mounts the housing lb.It is preferred that this be achieved through having the upper Zone ofportion ll include horizontally extending surfaces 23, 24 and 25 (FIG.4). The lower edge of body lit bears against surface 24. The parts arecoupled against accidental detachment as, for example, by employingbolts 26 (see FIG. 5) for this purpose.

The upper edge of housing lib defines a cylinder. This includesconcentrically disposed and spaced walls 27 and.

28 defining between them an upwardly facing cylinderchannel. Wall 28 isconveniently furnished by employing a separate ring unit and welding itin position so that, in effect, it is integral with the housing. Wall 27is formed with a port 29 to which is coupled the fitting 14 for thepurpose of introducing liquid into and allowing it to escape from thecylinder.

Upon the edge surface 23 of base portion 11 there is rotatably supporteda socket wrench 30. As shown in FIG. 4, the skirt portion of this wrenchextends downwardly to overlap the upper Zone of nut 21. ts bore facewill conform to the configuration of the nut. Therefore, when the Wrenchis turned the nut will be rotated.

With a view to effecting this rotation, it is preferred to have anannular series of teeth 31 in the upper edge of the wrench. These teethconveniently engage with the teeth of a gear 32 afiixed to the inner endof shaft 16. A suitable bearing structure such as 33 may be interposedbetween the shaft and the surface of the opening defined by flange 15.It will be apparent that as shaft 16 is rotated by handle 17, gear 32will turn. This will cause rotation of the socket wrench 3t and the nutengaged thereby. A load transmitting assembly forms a part of theapparatus and includes a unit comprising downwardly extending boss 34.The latter has its lower end recessed and threaded as at 35 so as toengage with the threads of bolt 29. The upper end of the unit is definedby a head 36 which is of sufficiently large diameter to overlap theupper end of the cylinder. Parts of the load transmitting assembly aredisposed within .the cylinder. Those conveniently include a singleannular body 3'7 having its inner and outer edges formed with grooveseach receiving suitable packing material 38. This will sealingly wipeagainst the adjacent faces of Walls 27 and 26. The assembly alsoincludes the plate 12 resting upon the upper face of body 37 engaged bythe underface of head 36.

Where an annular series of bolts and nuts mounted thereon are involvedin a seal to be established, then several tensioning mechanisms will beemployed. They will, for example, be spaced around the c'u'cumferencedefined by the bolt series to the extent of or 45. Thereupon they willbe caused to function and tension the bolts to which they are connected.Under these circumstances, rings 37 will extend beyond the groovedefining the cylinder housing. While under condition of tension, thenuts mounted by those bolts will be tightened. Thereafter, themechanisms will be deenergized, which will cause the piston elements tobe returned to initial positions under the action of springs 13'. Thenthe units are removed from the bolts to which they are attached.Following this, they will be shifted to cooperate with bolts disposed inpositions intermediate the bolts to which they were previously applied.After tensioning the then current bolts, the nuts mounted thereon aretightened. This'operation will be repeated until the entire series ofbolts and nuts applied thereto have been tensioned. Such procedure willbe feasible in the case of closely spaced bolts by virtue of recessingas indicated at 18 in FIG. 3.

As a consequence of following this technique, it is apparent that aneven tensioning of all bolts will occur and, with a. proper tighteningof the nuts mounted thereby,

an effective seal of equal tension-value throughout an entirecircumference will be established. Similar seals will be provided bycorresponding procedure in the case of rectangular, row, or otherconfigurations defining a bolt series. Obviously, a single bolt may alsobe properly tensioned and secured. If circular and indented orcastelated nuts are employed, the contour of the socket wrench may becorrespondingly modified.

Now considering the operation involved in one bolt of the series, itwill be understood, according to the illustrated embodiment, thatannular surfaces are defined by two members (for example the end flangesof conduits). Those members are provided with openings and the latterare brought to positions adjacent each other. A gasket structure ofsuitable material may be interposed between the members, in which caseit will also have openings aligning with the member openings. The boltswill be extended through the members and nuts will be mounted by thosebolts. Expedients such as lock washers will not ordinarily be resortedto.

A nut as in FIG. 4 will be ensleeved over the end of a bolt and the nutmounted thereby. The base portion of the housing will bear against thesurface 22 of the adjacent member. As previously brought out, the area19 of bearing contact will be adequate to assure against an indenting orother injury to the parts.

Accordingly, the base portion 11 of the housing will, in effect,encircle the nut 21. The latter will have an adequate area ofits facesin bearing contact with the faces of socket Wrench 30. The outer end ofthe bolt 20 will be enclosed within the boss 34 with the threads of thelatter engaging the bolt threads. If the nut has not been previouslyshifted to thrust against surface 22, then the socket wrench may beturned to assure this result. Liquid under pressure will no heintroduced through port 29. This will cause the ring assembly to risewithin the groove. Accordingly, the overlapping head portion 36 of theload transmitting assembly will be elevated. With such elevation, bolt20 will be placed under tension and elongated to some extent.

It will be understood, in this connection, that the reaction forces aretransmitted through the housing to surface 22. Thereupon, by means ofthe socket wrench or its equivalent, the nut 21which will have beenelevated from surface 22 as a consequence of the tensioning-will againbe rotated around the bolt to a point Where its underface firmly thrustsagainst the surface 22. Thereupon, the pressure within the cylinder isrelieved by permitting the liquid to escape through port 29 and toreturn the piston parts to their initial positions. As will beunderstood, by rotating the load transmitting assembly, head 36 and boss34 may be detached from the bolt.

To assist in such rotation and as shown in FIG. 2, the upper surface ofthe head is conveniently formed with notches 40. These may receive thefingers of the operator or else a tool manipulated by him to rotate thepiston as a unit. It will, of course, be understood that a similarprocedure will have been followed in coupling the load transmittingassembly with the bolt. The apparatus may now be elevated clear of agiven bolt and nut assembly and again applied to a bolt which now shouldbe tensioned.

As is apparent in a comparison of the dimensions present in FIG. 4 incontrast with those in FIG. 5, the latter figure illustrates a bolt 26of larger diameter than bolt 28 and a nut 21' also of larger area.However, the body portion If of the housing and the ring assembly 37 arethe same size. All that has been necessary to adapt the apparatus to thelarger bolt and nut assembly was for the operator to detach base portion11 through loosening bolts 26 and then removing it together with socketwrench 30. These parts include the load transmitting assembly and boss.A new load transmitting assembly involving a socket and threaded boss 41will be substituted for the removed parts. it will again have a headportion 42 corresponding to head 36. The socket wrench 43 will be ofless height. The wrench will also be telescopically disposed withreference to the housing. The base portion 44 of the housing may be of adifferent configuration than portion 11 so that proper support of theparts is assured in the manner previously described. In the examplesgiven in FIGS. 4 and 5, bolts of 1% diameter as against 2% diameter areinvolved together with corresponding sizes of nuts. It is apparent thatthe apparatus as in FIG. 5 will function as previously described inconnection with the structure of FIG. 4.

Thus, among others, the several objects of the invention as specificallyaforenoted are achieved. Obviously, numerous changes in construction andrearrangement of the parts may be resorted to without departing from thespirit of the invention as defined by the claims.

What I claim is:

1. A bolt tensioning apparatus including in combination a housing havingan upper face formed with an annular channel and a fluid conducting portcommunicating therewith, a load transmitting assembly comprising a ringwithin said channel, a head overlying said ring and an interiorlythreaded boss fixed with respect to said head and extending downwardlyinto said housing, said housing and boss being free of parts obstructingthe complete withdrawal of the boss under manual elevation of the headof said load transmitting assembly, said head being rotatable withrespect to said housing whereby to permit coupling and uncoupling of theboss threads with the threads of a bolt to be tensioned. said ring beingprojectable from said channel under the action of fluid pressure andthrusting throughout the entire area of its upper face against theunderside of said head to elevate said assembly, a nut-engaging wrenchmounted for movement within the lower end of said housing, and removablemeans for normally retaining said nut-engaging wrench in position withinsaid housing and said wrench being withdrawable from the housing uponsaid retaining means being detached therefrom.

2. A bolt tensioning apparatus including in combination a housing, aload transmitting assembly comprising a head overlying said housing, athreaded boss fixed with respect to said head and extending downwardlyinto said housing, said housing and boss being free of parts obstructingthe complete and ready withdrawal of the boss under manual elevation ofthe head of said load transmitting assembly, said head and boss beingrotatable as a unit with respect to said housing whereby to permitcoupling and uncoupling of the boss threads with the threads of a boltto be tensioned, a fluid pressure cylinder and a piston for mining partsof said housing and load transmitting assembly and acting against saidhead to project the latter and the boss, a nut-engaging wrench mountedfor movement within the lower end of said housing, and removable meansfor normally retaining said nut-engaging Wrench in position within saidhousing and said wrench being withdrawable from the housing upon saidretaining means being detached therefrom.

References Cited in the file of this patent UNITED STATES PATENTS DeMart June 19, 1962

1. A BOLT TENSIONING APPARATUS INCLUDING IN COMBINATION A HOUSING HAVINGAN UPPER FACE FORMED WITH AN ANNULAR CHANNEL AND A FLUID CONDUCTING PORTCOMMUNICATING THEREWITH, A LOAD TRANSMITTING ASSEMBLY COMPRISING A RINGWITHIN SAID CHANNEL, A HEAD OVERLYING SAID RING AND AN INTERIORLYTHREADED BOSS FIXED WITH RESPECT TO SAID HEAD AND EXTENDING DOWNWARDLYINTO SAID HOUSING, SAID HOUSING AND BOSS BEING FREE OF PARTS OBSTRUCTINGTHE COMPLETE WITHDRAWAL OF THE BOSS UNDER MANUAL ELEVATION OF THE HEADOF SAID LOAD TRANSMITTING ASSEMBLY, SAID HEAD BEING ROTATABLE WITHRESPECT TO SAID HOUSING WHEREBY TO PERMIT COUPLING AND UNCOUPLING OF THEBOSS THREADS WITH THE THREADS OF A BOLT TO BE TENSIONED, SAID RING BEINGPROJECTABLE FROM SAID CHANNEL UNDER THE ACTION OF FLUID PRESSURE ANDTHRUSTING THROUGHOUT THE ENTIRE AREA OF ITS UPPER FACE AGAINST THEUNDERSIDE OF SAID HEAD TO ELEVATE SAID ASSEMBLY, A NUT-ENGAGING WRENCHMOUNTED FOR MOVEMENT WITHIN THE LOWER END OF SAID HOUSING, AND REMOVABLEMEANS FOR NORMALLY RETAINING SAID NUT-ENGAGING WRENCH IN POSITION WITHINSAID HOUSING AND SAID WRENCH BEING WITHDRAWABLE FROM THE HOUSING UPONSAID RETAINING MEANS BEING DETACHED THEREFROM.